Patent GB-115270-A (GB)
IPC: A01B63/18
Abstract: 115,270. Cameron, W. W. May 3. 1917. Motor implements; ploughs; adjusting parts of implements; steering.- Ploughs 1 carried by a frame 2, 2a, 2<b> are raised or lowered by the rotation of a cranked shaft 4 which is adapted to be clutched to the hub of the land-wheel 3 by the operation of a lever 42. The cross-member 11 forming the front end of the plough frame has mounted in brackets 13, 14 rigidly secured to it a shaft 12 which is provided at one end with a crank-arm 12a connected by a link with a collar 15 on the shaft 4 and pivotally carries at its other end a lever 18 connected by a link to a second collar 18<c> on the shaft 4. The lever 18 raises or lowers the one side of the plough-carrying structure relatively to the shaft 4 and is locked in position by a ratchet secured to the shaft 12. The shaft 12 is turned to adjust the position of the plough-carrying frame as a whole relatively to the shaft 4.by a hand-lever 16 secured to the shaft 12 and locked by a ratchet 17 secured to the member 11. 'Brackets 9, 10 are mounted at each side of the plough-carrying frame and are bored to take guide-standards 7, 8 mounted on the brackets 6, 40, carrying the axle of the furrow wheel 5 and the land-side end of the shaft 4 respectively. These standards are bored to permit slight transverse movements of the plough-carrying frame relatively to the wheel frame. Rocking levers 19, 21 are pivoted at the top of the standards and are secured by links 20, 22 and springs 23, 24 to the brackets 9, 10 and the brackets 40, 6 respectively. The springs 23, 24 cushion the lowering of the plough frame and assist in raising it when the cranked shaft 4 is rotated. The arrangement for rotating the shaft 4 is shown in Figs. 9, 11, 12. The hub 47 of the wheel 3 is provided with ratchet teeth which are adapted to engage with one or other of two pawls mounted on a plate 45 keyed to the shaft 4. The pawls carry adjustable cam-engaging members 46 which bear against a cam 40<g> formed on the bracket 40. The raised portion 40<e> of the cam is so arranged that a pawl which has been in engagement with the ratchet teeth on the hub 47 is freed from these teeth when the cranked portion of the shaft 4 has just passed the dead centre with relation to the weight of the plough or with relation to the pull of the springs 23, 24. The weight of the plough or the pull of the springs then causes the shaft 4 and the pawls to rotate a little further until a projection 48<a>, on a spring- pressed plunger 48 which moves in bearings in arms extending from the bracket 40, enters a recess 45d in the plate 45 and so locks the shaft 4 with the ploughs in their raised or their lowered position. The second pawl which, while the first was engaged by the ratchet teeth, was held raised with its member 46 moving idly over the raised portion of the cam is prevented from engaging the teeth in its turn, until the lever 42 is moved, by its member 46 engaging a movable extension, Fig. 11, of the portion 40<e> of the cam. This extension is carried on a pivoted arm 44 connected by a link 43 with the lever 42. On pulling the lever, the extension is forced inwards against the pressure of a spring and the operating pawl is engaged by the teeth on the hub 47, the plunger 48 simultaneously being forced by a cam out of the recess 45d. The rear end of the plough frame is raised and lowered simultaneously with the front end by a bell-crank lever pivoted on a link secured to an adjustable collar on the stem of the rear wheel 37, this lever being connected by an adjustable link 27, 28 with a bell-crank lever pivoted on the shaft 11 and connected by a rod 25 with the upper end of the standard 8. The rear wheel 37 may be set to run in line with the ploughs or slightly inclined to them by adjusting the length of a rod 38 secured to an arm 39 extending from the stem 36 of the wheel. The connexion between the stem 36 and the arm 39 is made yielding to permit the wheel to move while the plough is turning. A locking-device is provided to hold the wheel rigid if necessary.